1. Field of the Invention
The present invention relates generally to equipment used in the lumbering industry, and more particularly to a portable sawmill having powered or automated means for hoisting a log onto a cutting platform or bed, lifting the log to the desired height and positioning the log for cutting, and removing cut boards from the mill.
2. Description of the Related Art
Portable sawmills are in common use in wooded areas throughout the world. Such portable sawmills are generally constructed on trailer platforms for towing from one location to another as the need arises. Sawmills, portable or otherwise, may employ a number of different saw principles, from circular saws to reciprocating blades to band saws having continuous blades.
The typical portable sawmill incorporates a band saw with the cutting portion of the blade oriented horizontally. However, such mills conventionally adjust the height of the saw mechanism for different cuts, with the log remaining stationary as the boards are cut from the log. Moreover, such conventional mills generally lack any means for loading a log onto the log support bed or platform, or for removing cut materials from the mill. Logs must be loaded by other means, e.g., manually or with a fork lift or other mechanized equipment, and cut boards must be manually removed from the mill. While many such portable mills are advertised as requiring only a single operator, in truth most such mills require at least one assistant to help load logs onto the cutting bed, position the logs properly for cutting, and remove cut boards from the mill, if any reasonably efficient production is to be maintained. A single operator can certainly operate such a mill, but the operator must take the time to load the next log for cutting, remove cut boards from the mill, etc., which greatly reduces production.
The present inventor is aware of various portable sawmills that have been developed in the past. An example of such is found in PCT publication WO 98/23420, published on Jun. 4, 1998. This publication describes (according to the drawings and English abstract) a small mill having the drive motor for the band saw offset from the major axis of the saw wheels to reduce torsional stress on the support rail for the saw.
Thus, a portable sawmill solving the aforementioned problems is desired.